1. Field of the Invention
The invention relates to a typewriter or similar machine with a print wheel disposed on a shaft drivable by a motor, the characters of which a printed by means of a hammer.
2. The Prior Art
Customarily such typewriters are designed in such a way that the print wheel is either seated directly on the motor shaft or on a rotational positioning shaft which can be driven by a motor by means of a gear. Customarily a step motor is used as a motor. When the character selected for printing is in the print position, printing is accomplished via a microprocessor of the electronically controlled typewriter. In most of the known typewriters of this type printing is accomplished by a magnet, the striker of which acts directly or indirectly on the back of the spoke of the print wheel which carries the selected character. As a result, these known devices require a print magnet besides the motor for the rotational positioning of the print wheel. Thus there are two drives which are comparatively expensive. Furthermore two drives together represent a corresponding mass which must be moved by the motor moving the carriage along the platen. Accordingly this motor has to be of a corresponding size. In addition, the print magnet often is in a position in which it obscures the view of the printed text. On the other hand, such a print magnet often is in the way when either the ribbon or the print wheel is to be exchanged. Such a mechanism is shown, for example, in German Patent No. DE-PS 30 14 286. This a comparatively complicated design requiring many components, furthermore its assembly is expensive.